// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "net/quic/test_tools/test_task_runner.h"

#include <algorithm>

#include "net/quic/test_tools/mock_clock.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace net {
namespace test {

    TestTaskRunner::TestTaskRunner(MockClock* clock)
        : clock_(clock)
    {
    }

    TestTaskRunner::~TestTaskRunner() { }

    bool TestTaskRunner::PostDelayedTask(const tracked_objects::Location& from_here,
        const base::Closure& task,
        base::TimeDelta delay)
    {
        EXPECT_GE(delay, base::TimeDelta());
        tasks_.push_back(PostedTask(from_here, task, clock_->NowInTicks(), delay,
            base::TestPendingTask::NESTABLE));
        return false;
    }

    bool TestTaskRunner::RunsTasksOnCurrentThread() const
    {
        return true;
    }

    const std::vector<PostedTask>& TestTaskRunner::GetPostedTasks() const
    {
        return tasks_;
    }

    void TestTaskRunner::RunNextTask()
    {
        // Find the next task to run, advance the time to the correct time
        // and then run the task.
        std::vector<PostedTask>::iterator next = FindNextTask();
        DCHECK(next != tasks_.end());
        clock_->AdvanceTime(QuicTime::Delta::FromMicroseconds(
            (next->GetTimeToRun() - clock_->NowInTicks()).InMicroseconds()));
        PostedTask task = *next;
        tasks_.erase(next);
        task.task.Run();
    }

    namespace {

        struct ShouldRunBeforeLessThan {
            bool operator()(const PostedTask& task1, const PostedTask& task2) const
            {
                return task1.ShouldRunBefore(task2);
            }
        };

    } // namespace

    std::vector<PostedTask>::iterator TestTaskRunner::FindNextTask()
    {
        return std::min_element(tasks_.begin(), tasks_.end(),
            ShouldRunBeforeLessThan());
    }

} // namespace test
} // namespace net
